Primary appendiceal cancer is rare, however, there has been a notable increase in its annual incidence from 0.63 per 100,000 in 2000 to 0.97 per 100,000 population in 2009 [1]. Although it can occur at in any age, it is most commonly diagnosed in the sixth and seventh decades of life [2]. The most common type of appendiceal cancer is adenocarcinoma, accounting for about 50–60 % of all appendiceal neoplasms, followed by neuroendocrine tumors [3].

Appendiceal adenocarcinomas may be incidentally discovered during the routine pathologic examination of the appendix after appendectomy for suspected acute appendicitis or detected by an abdominal CT scan done for patients with abdominal symptoms. Advanced appendiceal adenocarcinoma may present with vague abdominal discomfort and increasing abdominal girth [4]. The exact rate of metastatic appendiceal adenocarcinoma is unclear, due to the scarcity of cases, yet it is estimated to range between 23 % and 37 % [2,5].

The management of non-metastatic appendiceal adenocarcinoma is surgical. Right hemicolectomy is indicated in patients with T1 tumors with high-risk features, including high-grade histology, lymphovascular invasion, and/or positive margins after an appendectomy, otherwise, appendectomy alone may suffice. For T2-T4 tumors, complete staging with CT scanning is required to exclude distant metastasis before surgery. Appendiceal carcinomas have two main modes of metastases: peritoneal, especially with mucinous adenocarcinomas, and nodal metastases. Adjuvant chemotherapy with 5-fluorouracil/leucovorin or capecitabine with oxaliplatin may be indicated in stage III patients and stage II patients with high-risk features or inadequate nodal staging [5].

There is a paucity of data on the outcomes of surgical treatment of non-metastatic appendiceal adenocarcinoma. Also, a few studies investigated the predictors of overall survival (OS) in appendiceal adenocarcinoma. A SEER database analysis of 1404 patients with appendiceal adenocarcinoma found that older age, T4 tumors, N1-2 stage, poorly differentiated carcinoma, and distant metastasis were significantly predictive of poorer survival [6]. Another small single-center study including 49 appendiceal cancer patients reported female gender and low-grade adenocarcinoma to be associated with increased OS [7]. However, these previous analyses did not take into account some important prognosticators of survival such as patients’ comorbidities and functional status, pathologic parameters such as lymphovascular invasion, and adjuvant systemic treatment. It is unclear whether partial right colectomy, not including the hepatic flexure, is an adequate oncological treatment of appendiceal adenocarcinomas. We hypothesized that partial colectomy might have similar survival outcomes to classical right hemicolectomy in appendiceal adenocarcinomas. Therefore, we used the National Cancer Database (NCDB) to compare the outcomes of partial right colectomy and right hemicolectomy and to determine the predictors of OS after surgical treatment of stage I-III appendiceal adenocarcinoma.